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Better views of andromeda? + other questions


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Hello all!

I'm very new to astronomy, having lots of fun so far - even though I've mostly just been spinning the telescope around without much purpose, it has been really cool. I did manage to find and split Epsilon Lyrae, and I'm getting slowly acquainted with the constellations. I haven't posted much but I have been reading / absorbing while quietly doing my thing :)

Last night, my finderscope was absolutely useless. It's the stock x50 that came with my skyliner 200p, I checked that it was aligned before I started but in no time at all everything felt blurry and out of focus when looking through it. I think the finderscope lens must have gotten covered in dew?

I struggled on without using the finderscope and eventually managed to find Andromeda by looking through the main scope and star hopping (this took a while!). Now that I've found it once it should be easier next time.

After a few nights stargazing I do have some questions:

1/ Can you focus a finderscope? I tried twisting the end a little but it didn't seem to do anything

2/ I have a hard time getting sharp focus, it seems very fiddly getting that sweet spot. Is this normal? Is it a collimation issue? It's not so bad at 48x but gets harder with each higher power

3/ I tried a 'star test' with a high powered EP but at no point did I see anything resembling concentric rings?

4/ What can I do to improve my views of andromeda? The core was highly visible although basically just a fuzzy white ball, and it was very difficult to make out any details of the arms etc. Would darker skies help? I was observing on the patio last night but could move further down the garden if it will help. I'm also only 15mins drive from a dark sky site

Thanks in advance

- Lister

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Hi,

 

Yes you can focus a finder scope. You normally turn the front lens in or out. There will probably be a locking ring behind the cell housing that you should loosen first.

The 'sweet spot' will get smaller as you increase magnification. Don't forget that if you don't have electronic focus adjustment, touching the focus knob will set up vibrations that will be worse at higher magnification.

Collimation could well be the issue. Also so could be your patio, if it is not solid and you are walking around your mount.

Edited by Stargazer33
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I was looking at Andromeda last night too and can get nearby M32 and M110 in the same FOV at 42x magnification - 3 Galaxies all at once ?

In relation to sharpness , it is a good idea to focus on a nearby star and when it is tack sharp the Galaxy is as sharp as it's going to get at that location ... the light from M31's core takes 1.5 million years to reach us , pretty mind blowing ?

When I first got the 200P I used the kit finder for about 10 to 15 minutes finding it very difficult to get used to and just tried the red dot finder from my 130P instead and it was much better . I just stick my finger in the finder and rub the dew away every so often and would double check the fuzziness is not a dew problem rather than a focus problem before you start adjusting the finder .

Edited by Red Dwarfer
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1 hour ago, Lister said:

What can I do to improve my views of andromeda? The core was highly visible although basically just a fuzzy white ball, and it was very difficult to make out any details of the arms etc. Would darker skies help? I was observing on the patio last night but could move further down the garden if it will help. I'm also only 15mins drive from a dark sky site

Absolutely, for galaxies dark skies are the best answer. Detail in the Andromeda galaxy is always subtle, but light pollution washes out the outer parts very easily. Mind you, you skies can't be two bad if M110 was visible?

Good dark adaptation also helps. Your easy take anything up to 45 mins say to get fully adapted, on look at a bright phone or streetlight starts the clock again. Once achieved you will see much more of the faint stuff.

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Hello! sounds like you're having a lot of fun! A tetrad finder will fix the problem with you're finder scope, it is honestly the best finder you can buy.

Getting sharp focus at higher magnifications is tricky, especially with a single speed focuser. The threshold for sharp focus gets smaller the more magnification you add, how much of course depends on the eyepiece you use.

Andromeda will always be smudge, unless you have a really big scope (15" or larger). But at a dark sky you should be able to make out a dark lane or two. 

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Thanks for your replies :)

I set up on the patio as its solid ground, its darker toward the back of the garden (and more shielded from the neighbours lights)  but id be setting up on grass so it might introduce wobble. 

So it won't do any harm wiping the top of the finderscope if it gets too dewy? I will be upgrading it but it won't be anytime soon, been a tough month between the mot and the new scope (my original budget for a starter scope was about £60, whoopsie) 

I'm also interested in anything else to look out for, if you have your own favourites id be happy to hear them. And yes its been a lot of fun so far! 

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A firm lawn is sometimes better than a patio for keeping vibrations at bay - I think the earth absorbs them to some extent ?

You can make a dew shield for the finderscope by wrapping a piece of card around the existing one to extend it a few inches. An elastic band or some tape should hold it in place.

Edited by John
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When setting up on grass I put the feet on some ceramic tiles left over from a kitchen re-fit, this prevents sinking.

40 minutes ago, Lister said:

I'm also interested in anything else to look out for, if you have your own favourites id be happy to hear them. And yes its been a lot of fun so far! 

You found Epsilon Lyrae, well done. Not far away is M57 the Ring Nebula which your scope will show well(once you have found it use the highest power you have.)

A great book to get you started is Turn Left at Orion. This takes you through the seasons and highlights objects for small scopes with directions on how to find them and sketches of what to expect when you find them.

Good luck and keep enjoying the night sky.

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1 minute ago, Astro Imp said:

When setting up on grass I put the feet on some ceramic tiles left over from a kitchen re-fit, this prevents sinking.

You found Epsilon Lyrae, well done. Not far away is M57 the Ring Nebula which your scope will show well(once you have found it use the highest power you have.)

A great book to get you started is Turn Left at Orion. This takes you through the seasons and highlights objects for small scopes with directions on how to find them and sketches of what to expect when you find them.

Good luck and keep enjoying the night sky.

I have tlao, but i can't read it in the dark so I'm not sure how best to proceed with it.  Do i pick an object or two and try and memorise their location before i start observing? 

40 minutes ago, John said:

A firm lawn is sometimes better than a patio for keeping vibrations at bay - I think the earth absorbs them to some extent ?

You can make a dew shield for the finderscope by wrapping a piece of card around the existing one to extend it a few inches. An elastic band or some tape should hold it in place.

Top tip, i will try the dew shield. 

I also had an unintended observation last night - i was looking at a star near andromeda, i think it was alpheratz, really concentrating and trying to get the best focus, when suddenly a plane flew right across my fov -  It was huge, it filled the whole eyepiece and went whooshing past, actually made me jump! 

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4 minutes ago, Lister said:

I have tlao, but i can't read it in the dark so I'm not sure how best to proceed with it.  Do i pick an object or two and try and memorise their location before i start observing? 

Get a red torch - red light doesn't harm your dark adaptation much, but it will allow you to read the book. If I were you I'd get an adjustable one, as you'll probably want a brighter light at home than at a dark site.

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40 minutes ago, Lister said:

 It was huge, it filled the whole eyepiece and went whooshing past, actually made me jump! 

It really can be quite a shock when that happens, can't it?

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When using the standard 9x50 finder, keep BOTH eyes open?

Sounds daft, but with both eyes open, you'll see the original image with one eye, the magnified with the other, and when the two overlap, your on target, can't get any easier, though a RACI (Right Angle Corrected Image) finder scope may help in some circumstances, but did not help me at first?  Still some further testing on  my RACI once the new 'O' rings arrive, first test failed?

As for focusing the finder, there's a knurled ring toward the front of the finder, loosen it, the rotate the end section until focus is achieved, then lock down, this only needs one setup, best done during the day, making sure also that the finder is totally aligned with the scope.

As for better views M31, from my garden, the view is pants, just the basic core, but away from home, a darker site, I need the 32mm 2" eyepiece as M31 now fills the view, such is the difference from a dark site, its like having a different scope!!

Some folk mention a Telrad finder! Ive had two, but still can't use it without wearing glasses, and for the rest of my observing I don't wear glasses, so the Telrad sold, but I find the standard finder easier to use now,  especially keeping both eyes open, and from experience, the Telrad only shows the same image that your eyes see  ( un-magnified ). But you won't know until you try one.

Welcome to the SGL.

Edited by Charic
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I solved finding things with my 200P with an adapter that lets me mount 2 finders at the same time (there is a guy in Poland printing them with a 3D printer and flogging them on the well known auction site for about £8).  Then I got a cheap and cheerful Skywatcher unmagnified RDF finder (I think Celestron do a similar one on the same shoe mount) and a RACI magnified finder.  I mount both these on the adapter.  The PDF position means I can't quite align it spot on, but it is close enough.  I get the RACI spot on with the EP.  Then when I find the area of the sky I want I pick a close star to where I want to be and find it in the RDF.  The way things are set-up if I have something OK in the RDF I know its in the RACI field of view.  I then centre things up in the RACI and the star is spot on in the EP.  Using this method I've gone from failing to find something and giving up after searching aimlessly for 20 minutes to being able to find any object I can see with my naked eye in the EP <30 seconds.  Once you know where you are relative to something you perhaps can't see with the naked eye it makes finding it much more possible.   I can't recommend the combination finder approach highly enough.  It made my telescope useable when I can't be bothered to use the Goto.

 

NB: There is currently a RACI for sale in the classifieds section.

Edited by JOC
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On 26/09/2017 at 18:10, Lister said:

I'm also interested in anything else to look out for, if you have your own favourites id be happy to hear them. And yes its been a lot of fun so far! 

At the moment when skies are cloudless, double stars are my current occupation ( due to my location at this time of the year when a zillion light bulbs hang pointlessly illuminated so increases light pol by that said zillion times) there some fantastic doubles to observe, just do a search and some threads are full of list and info. The colours can be fantastic and most can be seen with a fair amount of light pol and without too much mag.

A lesser mentioned double which I love is WZ CAS, its in cassiopeia, 1.3 degrees from Caph, just google it or search in stellarium etc.

 

I agree with the suggestion of the Telrad, best bit of kit you can buy to get you around the night sky, even tho I have an AZ goto, I still use my Telrad when setting up and sometimes rather than punch the info in the goto, I will just use the telrad and direct the scope to the target.

Enjoy

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On 9/26/2017 at 18:10, Lister said:

I'm also interested in anything else to look out for, if you have your own favourites id be happy to hear them. And yes its been a lot of fun so far! 

The Double cluster in perseus (ngc884/869) is nice and easy to find (about half way between Cassiopeia and Perseus) and quite bright.

Dave...

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